Perhaps you should try some spelling variations:
cong thanh » dong thanh, cong trinh, cong tan
hien xanh » hien hanh, hien nhanh, chieu xanh
toan thuc » toan hoc, dan thuc, nhan thuc
thuc hung » thuc chung, thuc nhung, thuc dung
cong than » cong thang, cong tan, cong thai
phan cac » phan dau, phan lap, phan van

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: hoc hien xanh - tinh toan thuc hung ((cong than) or (cong thanh)) ((phan cac) OR (nhan cach))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: hoc hien xanh - tinh toan thuc hung ((cong than) OR (cong thanh)) ((phan cac) OR (nhan cach)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "hoc hien xanh - tinh toan thuc hung ((cong than) or (cong thanh)) ((phan cac) OR (nhan cach))".
• Adding a wildcard symbol may retrieve word variants: hoc hien xanh - tinh toan thuc hung ((cong than) or (cong thanh)) ((phan cac) OR (nhan cach))*.